Induction heat transformer



55 2- 9 39 G. B. ELY 2,171,080 I INDUCTION HEAT TRANSFORMER Filed May 4,1938 2 Sheets-Sheet l ATTO R N EYS Aug. 29, 1939. cs. B. ELY 2,171,080

INDUCTION HEAT TRANSFORMER Filed May 4, 1938 4 2 Sheets-Sheet 2 a i U; Q

[Ill/[I i; w E k I, E Q}. Q muulmju H 2;. xgmm Q B m g Patented Aug. 29,1939 UNITED STATES PATENT OFFICE 7 6 Claims.

This invention relates'to electrical heating apparatus and moreparticularly to an induction transformer unit type using alternatingcurrent and including an impedance coil composed of a conductor ofmagnetic character and a special characteristic core and outer casing ofa similar magnetic nature.

The invention has for its principal object to secure higher efficiencywith compactness of structure and minimization of cost of production aswell as in maintenance and operation.

Another object is to provide standard induction heat transformer unitsof a given size and structural arrangement so as to be'variablyassembled in heating apparatus installations of different ca pacities.

Other objects and advantages to be attained will hereinafter more fullyappear in the following description. 7 g

The invention consists in the novel general construction and assemblyand in parts and combinations and arrangements of parts as hereinafterset forth and claimed, reference being had to the accompanying drawingsillustrating a practical adaptation of the invention, and in whichFigure 1 is a view of a heating apparatus partly in side elevation andpartly in vertical section;

Figure 2 is a view more or less schematic in 30 character andillustrating a heattransformer unit 'in'end elevation;

Figure 3 is a fragmentary view, on an enlarged scale, showing one cornerportion of a heat transformer unit in end elevation; and

Figure 4 is a fragmentary sectional view on the same scale as Figure 3,the section being taken substantially on the line 4-4 of Figure 2.

Referring now to the drawings, the heat transformer unit will be firstdescribed. This unit which is conventionally shown fully assembled inFigure 2, but in structural detail in Figure 3, is

of the type having only a primary winding, and

culation of air therethrough, while for practical.

50 interchangeable assembly of the units the same Y are preferably madein square or rectangular cubical form.

Referring now more particularly to Figure 2,

the unit designated generally by the numeral Ill,

55 comprises a hollow core ll of square cross section, said coreincluding four outer members I2 in overlapped abutting relation and fourinner members 13 of smaller transverse dimensions in the same overlappedabutting relation to each other. Each member and 13 of the core ilcomprises a sheet of steel or characteristic alloy the formula of whichis in accordance with the size and number of wire turns of the coilwound about the core to produce the desired degree of heat within thecore and surrounding shell, as will presently more fully appear. Asshown more clearly in Figure 3, the sheets comprising the core membersl2 and i3 as well as the members l4, comprising the outer shell, areformed by rebending the sheets composing the respective memberstortuously throughout so as to produce a multiplicity of closelyarranged and alternately opposed triangular passageways i5 extendingthroughout the length of the unit and open at their opposite ends.

Preferably, rolled supplemental sheets forming tubes (6 are placed inthe respective passageways IS in circumferential contact with the threetriangular walls of the passageways, one marginal portion i l of eachrolled sheet being turned diametrically inward across the bore of thetube l6 and dividing the latter into two separate longitudinalpassageways.

It is here noted that the peculiar folding and rebending of the sheetscomprising the core and shell elements of the unit not only produces amultiplicity of passa ways through the unit with maximum surface ea, butbetter heat generation and conductivity is attained due to thecontinuity of the sheets and the avoidance of joints except at intervalswhere the bases of the triangular formations abut each other, thejoining of the parts being effected by a welding process so as to makethe structure rigid without detracting from the magnetic and heatconducting qualities of the metal.

The space between the core and outer shell of the unit is occupied bythe solenoid or impedance coil l8 comprising a suitable insulated copperwire wound about the core and properly insulated therefrom, said wirebeing of a size and the number of turns thereof about the core beingsuch, that with the steel or characteristic alloy comprising the coreand outer shellof the requisite formula, 9. temperature of approximately200 degrees Fahrenheit is produced in the core and shell when the coilis energized. In this connection, it is noted that the coil i8 does notextend the full length of the unit I0, but

' terminates short of each end thereof, and open ended tubular membersit, of rectangular cross section, are inserted in the space between thecore ii and outer shell members i i in close rela tion to each other andpreferably welded in place.

By the construction of a heat transformer unit as herein described, itis obvious thatair passed through the multiplicity of passageways in thecore and outer shell of the unit will become thoroughly heated due tothe contact with the extensive surface area of said passageways whichmakes the units practically adaptable for use in heating apparatus formany purposes.

In Figure 1 of the drawings the heat transformer units of the presentinvention are shown as incorporated in a heating apparatus 2@, saidapparatus comprising a body shell having an air intake manifold orchamber 2i and an outlet chamber or manifold 22. Between the twochambers 2i and 22 a battery of heat transformer units ID areinterposed, said units being superposed one upon the other in anarrangement whereby the air from the chamber 2! has to pass therethroughinto the outlet chamber or manifold 22.

Preferably, provision is made for passing the air separately through therespective heat transformers it As shown, a blower 23 is located in thelower portion of the intake chamber or manifold chamber 2i below -an airfilter 26 throughwhich the air passes before entering the blower, andfrom the discharge outlet 25 of the blower separate conduits 26 leadinto the re spective heat transformer units ML In this con-- have aplurality of conduits branched therefrom trolling device (not shown) maybe provided as with other types of electrical or other heatingapparatus.

The present inventive idea lies mainly within the peculiarcharacteristics of the heat transformer unit itself, not only as to itsprinciple of construction and operation, but in itsready adaptabilityfor incorporation interchangeably in heating apparatus of various sizesand capacities, and particularly as to its high efliciency I andeconomic advantages.

It is obvious that the folding and formation of the sheets comprisingthe core and outer shell of the unit admits of considerable variationand that other structural modifications may be made within the spiritand scope of the invention as 5 defined by the appended claims. Theinvention, therefore, is not limited to the specific construc= tion andarrangements shown in the accompanyingdrawings.

What is claimed: 1. An induction heat transformer comprising a core ofmagnetic sheet metal folded and reand outer shell each formed ofmagnetic sheet metal folded and rebent to provide a multiplicity ofpassageways therethrough with extensive surface exposure, and aninterposed impedance coil comprising a primary winding about said core.

4. In a heat transformer unit, an open core of magnetic metal, said corebeing of generally square cross section and comprising separate membersformed of sheets of its characteristic metal folded and rebenttortuously to provide a multiplicity of adjoining triangular open endedpassageways, a multiplicity of tubular members of like characteristicmetal and formation as said ;core, and an interposed impedance coilcomprising a primary winding about said core.-

' 5. In a heating apparatus, a casing having an air intake chamber andan air outlet chamber, and a unitary system of induction heattransformers interposed between said chambers, each transformer unithaving a core and anouter shell of magnetic sheet metal, each formed toprovide a multiplicity of passageways therethrough, and an interposedimpedance coil comprising a pri== mary winding about said core.

6. In a heating apparatus, a casing having an air intake chamber and anair outlet chamber, a

battery of separate but adjoining, generally rectangular, induction heattransformer units interposed between said chambers, the respectivetransformer units each including a rectangular core and-acorrespondingly square outer shell, each having parallel pmagewaystherethrough, the core being built-up and including separate oblongsections formed from sheets of magnetic metal folded and rebent to formthe passageways in the core and the outer shell comprising similaroblong sections formed from the same charac-' teristic sheet metal, andan interposed impedance coil between the core and outer shell of eachunit, said coil comprising a primary winding I GEORGE nsLY.

about the core.

